Email Hosting Providers

SPFSPF

SPF Usage Statistics · Download List of All Websites using SPF

The Sender Policy Framework is an open standard specifying a technical method to prevent sender address forgery.

Google Apps for BusinessGoogle Apps for Business

Google Apps for Business Usage Statistics · Download List of All Websites using Google Apps for Business

Web-based email, calendar, and documents for teams. Renamed to Google Apps for Work, but now known as G Suite from Google Cloud.

Business Email Hosting

SSL Certificates

SSL by DefaultSSL by Default

SSL by Default Usage Statistics · Download List of All Websites using SSL by Default

The website redirects traffic to an HTTPS/SSL version by default.

Common Name InvalidCommon Name Invalid

Common Name Invalid Usage Statistics · Download List of All Websites using Common Name Invalid

The Common Name/SAN value of this websites SSL certificate does not correspond to the domain name.

Web Servers

ApacheApache

Apache Usage Statistics · Download List of All Websites using Apache

Apache has been the most popular web server on the Internet since April 1996.

Operating Systems and Servers